小鼠单纯肝切除后再生肝组织内大小核分裂相和卵圆细胞的观察

目的:探究C57小鼠单纯2/3肝切除后肝组织内与再生和肝干细胞有关的病理形态学变化及其意义.方法:在4个对照组(正常组、假手术组、倒千里光碱组和倒千里光碱2/3肝切除组)的参照下,观察实验组C57小鼠单纯2/3肝切除后不同时间肝脏病理形态变化(核分裂相和卵圆细胞等)和CK19、AFP免疫组化检测情况.结果:单纯2/3肝切除后小鼠均出现不同程度的成熟肝细胞通过大核分裂相分裂增生、轻重不等的小胆管/终末胆管增生反应和个别例中有类似于倒千里光碱肝切除模型组的卵圆细胞增生;尤其还有大小核分裂相分布等一些文献未提及的形态学改变.结论:本研究提出肝流域假说的初步设想:肝内成体干细胞存在于小胆管/终末胆管附近,是肝主质细胞的重要源头;在其向中央静脉方向的流向上产生各级分化程度不同的子代(自卵圆细胞到小肝细胞、成熟肝细胞),沿肝板形成该流域干流;而经由血流到达肝脏的过客性干细胞可不同程度地在不同区段作为该流域的支流汇入干流并转分化为肝系细胞.

Observation of big and small mitosis and oval cell emergence in regenerated liver tissue after partial hepatectomy

Objective: To observe pathologic changes of regenerated liver tissue in mice with 2/3 hepatectomy (PH). Methods: Liver oval cell (OC), big and small mitosis and immunohistochemical staining of CK19 and AFP were observed in C57 mice at several time points after PH, and the results were compared with those of 4 control groups:normal group,pseudo-operation group,retrorsine (RS) group and RS/PH group. Results: Proliferation of mature hepatocytes and evident or mild proliferative reaction were observed in the small bile duct/COH epithelia in all cases. Emergence of OC was observed in individual cases in PH group, which resembled that in RS/PH group. The distribution of small mitosis were observed for the first time. Conclusion: The present study proposes a new hypothesis-liver valley hypothesis-adult liver stem cells, mainly locate in and about the terminal bile duct, probably are the important source of hepatocyte lineage cells; they replicate themselves and produce their progeny from oval cells to small hepatocytes and to mature hepatocytes; and when moving from the portal area to the central vein, the cells form the mainstream of the valley. Meanwhile, some stem cells from other organs, bone marrow stem cells for example, pass the liver through blood way and some of them turn into hepatocyte lineage cells and converge into the mainstream at different sites as affluents.